Distillation apparatus



Jan. 18,1927. 1,614,791

' E. R. HAMILTON DISTILLATION APPARATUS Filed Nov 1, 1923 lnvenTo1. Earl R. Horn'HTon byMMMM I Patented .len. l8, 19237..

srarss titer DISTILLATION APPARATUS.

Application filed November 1, 1323. Serial lilo. 672,099.

more effective and complete distillation of the material with which the apparatus is charged.

A. further object of the invention is to provide for the fractional collection and delivery of the pure distillate and also to save the more impure distillate.

A further obj ect of the invention is to provide a continuous distillation apparatus in which the circulation of the charge is maintained by the action of gravity. 1

Another object oft-he invention is to provide a distillationapparatus having separate chambers for the material, each of which may be maintained at a diiierent temperature, while the-apparatus is heated from a single source of heat.

A further object of the invention is to provide a distillation apparatus in which the more violent reaction of the fresh charge will take place in the presenceot a lower temperature than that linallyemployed.

A further object of the invention is to provide a continuously operated distillation apparatus which will not be subject to so great pressures from the volatile products of re action as in usual intermittently operated retorts.

More particularly the invention relates to in'iprovements inapparatus for manufacturing nitric acid from a suit-able nitrate and sulphuric acid. In the usual process of malting nitric acid the nitrate and sulphuric acid are placed in a cool or slightly warm retort which is then highly heated causing the chemicals to react and give off nitric acid which is collected and delivered to a suitable condensing apparatus. After the nitric acid has been formed and expelled from the retort, the spent sulphuric acid and the sulphates which are formed during the process are run oil and the retort allowed to stand until cool, after which the retortis again charged with nitrate and sulphuric acid and the process repeated. Thus the process is an intermittent one.

The present invention comprises a retort,

which is particularly designed for continue ous operation, but which is capable of intermittent use, having a plurality of communlcating chambers, preferably concentrically late which is expelled from arranged, and through which the material is progressively passed by the action of gravity and the material progressively heated during its passage through the-chambers.

Means are preferably provided for collecting and discharging the distillate which is produced from the material in oneor more of the chambers, which is subjected to a lesser degree of heat, separately from that which chambers. 1

In'the particular embodiment of the invention disclosed herein the retort comprises an inner container havinga plurality'of concentric communicating chambers located within an' outer container which entirely surrounds the inner container and forms a jacket there-for. Thecharge is introduced into the innermost chamberand then passes in turn through each next'outer chamber until it reaches the outermost chamber and is discharged therefrom in the continuous op eration of the device through an outlet pipe which communicates with'the outer container at a predetermined distance above its bottom, thereby maintaining a sufficient amount 7 of the fluid charge in the space between the inner and outer containers to form a liquid jacket for the inner container and its cham- The retort is further provided with a hood for the outer chamber and with one or more hoods for collecting the distillate formed in the inner chamber solthat the distillates formed in selected inner chambers may be kept separate from the more impure distilthe' partially spent charge; 7

By reason of this construction a distillation apparatus is provided in which the chemical. reactions may be produced with a minimum amount offuel consumption, thus avoiding much less of fuel necessitated in intermittently operated'systems from the required cooling down of the retort to permit the removal of the residuum after the distillation of the charge is completed.

Another object of the invention is to provide a retort which will have a relatively long life. A retort which is intermittently operated is subject to wide variations in temperature due to the cooling down and reheating thereof which causes such contractions and expansions that the retort is likely to crack or to break away from its support. Furthermore, if the retort is not is in a more highly heated chamber or V coolechsnfiioiently beforerecharging, a cool 7 forehlessssiibljeot,to-serious strains oi? expan- ;sien-andvcontraction. l'l heausual. intermittently operated retort ..oo1npr ises-l ,1nere1y asingle vessel for holding -the charge a-nid in which i the charge lies 7 (against the-inner? face 01"" the wall, the outer izfiaceoo'f 1 which. isq-subjected to: the, flames of heat. The inner face of the wallet; the re- -tort- -is thuseexposedito the-strong -c rrosive niLChlOIhgOf i the raw nitrates -.ia-nd strong" sulpliuriciacid-Whic-h, in their heatedcondition,

z'are -veryaeac-tive. In the retort embodyingthe present: inventionthe bottom of the reitortaisi never- -ex-posed to: the strongly corro- :S'IVGl'ZIOlJLOIl of theifresh 'chai geqas the greater iparti oiithe reaction takes. place within, the 1 innermostecompartment,- the .walls of which narea notqhighly heated and which are snore or, less protected-by: the partially spent pori tiion efzthe :charge.

Usual intermittently operated retorts' are "of; a ilarge .rcapacity capable of containing from .Jfive hundred atO tWelvehundred apounds, wrnore oer :less, of nitrate with the :necessaryamount of; sulphuric acid. :Unless thisw-amountz ofi chaizge is heated veryqcare fully the first reaction between the chemiica-ls is rviolentvand: the products of reaction zqgiveneoffwarerof such large i volume that all parts-of; the :retort are-subjected to heavy ;;pr,essure,- SLlfllClGIllTlILSOHIQ instances to' blow :o :the top ofwth'eiretoit, or'toitorce the distillate through; any: slight open ings which 'may; existin the: oint "between the =oover i and wall of the retort. In the former case the -Lpparatus would be destroyed, while in the latter-case anappreciable:amount otdistillatei-is lostiand" the operatorsgreatly, incon i ven ienced zby :suchescape of the obnoxious distillate.

i'By reason of the ;-present invention a charge may "ibe' introduced practi cally' continuou'sly fl'IliSlIlflll quantities-and violent reactions-at; any. time avoided. '1 Furthermore,

--the continuouslyooperated retort may be made-of lighterconstruction with no danger that. hhGiTGtOI'U-Wlll break by excessive pres- .sure,.-or; thatiany appreciablcainount of dis ti-IlateHWill-escape.

The, presentsinvention permits the use ofsma llera condensing apparatus since in in- .terniittentlyzoperated retorts the condensing system must-beef suiiicient capacity to care liei'ci for the excessive amount of distillate which is formed during tl'iestage ofinost violent reaction in the retort, While in the present invention the amount of distillate which is generated'in the retort is substantially constant and the condensing system need, thereiforc, be no larger than is necessary to take care of the usual ainountof distillate. Furthermore, Where the distillate is delivered to the condenser 'at a substantially constant .i'atc, a-constant fiowiof cooling fluid :may be provided andithe danger of sudden :ovcrhing or excessive cooling ot-theparts of the condenser and consequent breakage avoided.

One ol the specific objects otthe invention is to provide a distillation apparatuszitor producing nitric acidand 'other volatile products in which the, charge benoonservedaand"utilized"to its'liinitr ili'faiitric acid is made in an intermittently:operated retort the acid is lik'elypto be decomposed by long contact 1 with the hot walls iiOfl the vr'ei'iort during the final .smgmt the process when the retort ,is highly heat'ed-to drive oil the last remnants OliillGwDlhl'lCt.ZlGiCl. In

tlJ'CODtlHUOHSl Y operated retort: Oil the charactor disclosed herein the distillate lSffOT-IHQLQ a at approximately thesaineyra-fe. i llhei tend-j encyot the chemicals to boil'over during tlie nothing stage, at whichtimeithe'reaction is very violent, and the-consequent discharge of an impure product, 15- avoided.

The pure n tric acid iscolleotedand dishaiged separately fIOlll' themore xorkless' im pure product produced by the "final llltfdllin o; of theresiduuin, and'the TLlSe 'Of-di relatively' i small condensing apparatus is "required. i i

Other objects and rfeaturescot the; invenl tionwill inoredully"appear from'ztheffol lowing description and the accompanying,

dravving-and will-he; particularlvpointed out in theclaims. V g r in the drawing;

distillation apparatus embodying-the invention; V I

Fig; 2 a vertical. sectional view through n lo a series of retorts which may be s ucces'sively employed. Y

Only such parts of "the complete distillation apparatus are illustrated .asaa-i'e 'neces" sary to showits construction: andineans'oi' operation, it being understood that theretort may be used in con u ction with any typeoi' condenser or other apparatus usually employed.

The distillation apparatus llll-lSlL-l'fltQCl n designed particularly for tli8011- tinuous distillation of material, but it- -is-so constructed that it may be ialsooi-isediii-terinittently. v w

T is preferred embodiment of1 the invena. l. isa vertical sectionallviewithrough lierred lioi'm oi'ifurnaceand-retort of a pipe 20 and. the pipe 17.

tion shown comprises a furnace 1, which may be of any usual character, provided with a fire box 2 and having mounted therein a retort which comprises an outer container having a shell 3 provided with suitable out- 'ardly projecting lugs 4 which rest upon a ledge in the furnace wall. The preferred form of retort. is of bowl shape and comprises a hemi-spherical bottom portion 5 which is provided at its lower end with a tangentially extending outlet. conduit 6 which communicates with a Y-shaped conduit 7 the lower branch of which is connected to a discharge pipe 8 having a suitable valve 9 by which the outlet may be opened or closed at will. By reason. of this construction the entire residuum of the charge may be drawn off when the device is used intermittently as will hereinafter be more fully described. The other branch 10 of the Y- shaped conduit extends upwardly and is connected by one or more intermediate conduits 11 to an upper Y-shaped conduit 12 having a vertical passage 13 provided with an open end and a lateral branch let extending through the wall of the furnace and provided with a suitable flange by means of which it may be attached to a suitable pipe to'discharge the residuum into a receptacle or other container when the apparatus is operated continuously.

The upper portion of the shell 3is provided with an annular flange 15 to which is secured a preferably arch-shaped cover or top 16 having an upwardly extending pipe 17 which projects through the top 18 of the furnace and is provided with an annular offset flange 19 to receive the end of a discharge pipe 20 for the distillates and also provides a receptacle 21 for a suitable packing to hermetically seal the joint between the The cover 16 is also provided with an upwardly extending pipe 22 having an oifsetannular flange 23 which provides a'packing space 24; for the inlet pipe 25 which extends upwardly from a hood 26 for collecting the purer distillate as will hereinafter be more fully described. The cover 16 is likewise provided with another upwardly extending-pipe 27 having an offset flange 28 to provide a packing recess 29 surrounding a pipe 30 which extends upwardly from the hood 26 and provides for the discharge of the purer distillate.

In the preferred apparatus as illustrated in the accompanying drawings the furnace wholly encloses the retort so that the domeshaped cover 16 is protected from the cooling action of the atmosphere and is in fact maintained in a suthciently heated conditionto prevent condensation of water and acid vapors on the inside of the cover .which would attack the iron of the cover and also drop back into the receptacle and thereby decrease the efiiciency of the apparatus.

The retort also comprises an inner container having a preferably bowl-shaped shell 31, the outer surface of which isprovided with downwardly extending legs 32 which rest upon suitable shoulders 33 projecting from the inner face of the outer shell3. The

horizontal upper edge 34 of the shell 31 is well below the top of the upper edge 35 of the outer container 3 and is also located above the level of the outlet pipe 14: so that when the inner container is provided with a continuous, or substantially continuous, supply of material which-will overflow overthe edge 3% of the inner container into the outer container the spent residuum is finally caused to be discharged by the action of gravity through the outlet 1d.

The inner container desirably is provided with one or more vertical concentric partitions which divide the inner container into a series of chambers through which the charge is progressively forced and progressively heated during its passage to the outer container.

In the preferred embodiment of the in vention disclosed the shell 31 of the inner container is provided near its bottom with an annular rib presenting a shoulder 36 upon which a cylindrical partition 37 is mounted providing an innermost charging and mixing chamber 38. A plurality of apertures 39 are provided in the lower part ofthe par tition preferably at the junction of the pan tition, with the shoulder 36 of said annular rib, so that material charged into the innermost chamber will be caused to pass through the apertures 39 into the next outer chamber. The wall 37 of the innermost chamber extends well above the level of the edge 34 of the inner container so that the innermost chamber may be suppliedwith suliicient material' to cause the material to overflow the all 34. into the outermost chamber.

The shell 31'of the inner container is also provided with a second annular rib presenting a horizontal shoulder 40 upon which the vertical cylindrical wall 41-1 of'the hood 26 is seated, thus forming another partition providing a chamber 42 which is concentric with respect to the chamber 38. The cylindrical wall 4:1 of the hood is also provided near its lower end, preferably adjacent the shoulder 420 of the annular rib. with a plurality of apertures 43 through which the charge flows into the chamber 44 between the hood and the shell of the-inner container.

In the continuous operation of the apparatus material is charged into the innermost container until its level is above the level of the edge 34 of the inner container where upon the liquid will flow through the aperture 39 into the next outer chamber 42, thence through the apertures-43 into the chamber 141, and will thence overflow the edge 34 of the inner container into the outer Cir v contaiinertuntils it: ifilvlSli thev spaceibetweemthe annernandzou-ter containers :to theiilevel of the idischarge outlet 14,- wihereupon the'excess i-oi'umatenial' will be- ;dischargcd: throughqsaid 'zoutlet, During this -aoperation of the apparatus thexheat' of: ther'lurnace which is. c appliedfto:thefibottoin Lofthe-shell oithe .outer container :will heat" tl18,111ttt]3litl l)8 tween thewallsiofrthe inneruand outer con- Jt ainers iZtDtl the amateriah thus uheated rW ill transmit niore :or less of :1 s heat through the wall .Blcttherinner container utothennatenialcwithinz'thc concentric chambers ofthe 'iHRQIQCOZTtEUIlHBl. pAssthezinateriah of the (charge iis pcaaused to pass progressively thronghtthe:apertures 89 andASywhich are.

located adjacent to the shell-oftheinner container, it will? be progressively. heated in thessuc cessiverchambers and: .after overflow- ,ingctheaedge al-zofithe inner container will she .znnich more 1 lnnhly :heated :in 1 the outer v oentaziner. :Thus the charge is subjected -first :tosa: relatively low degreeof} heat and thereafter to progressively increasing degreesf otrheatt in the successive chambers until-1" itinallysubiected to? the? highest? heat :in the outermost; chamheraaridathe distillate completely {driven oiitherein.

:;-By 2 reason of: the construction described the purer udistillaite which is produced in .the iohanibersfiS ia nd =42: by-j'the initial reactionco'f the ,chernicals'ivhen tsubjectedi toms same condenser; or through 1 other devices usi-ially employed: in distillation apparatus as; will: be readily understood. Thus; a, fracti-onal 1 distillation. apparatus is providedv 1n 'XSElfl'lCh the purer di stillates in ay; be collected separately from: the more impure ,distillates whichaare produced duringz the final stage :of' the; process in which 1 the charge; is; high 1y; heated: to drive oifthellast remnants of the distillate in which "case: the distillate is some; times more or less decomposed by reashell of'the' outer-container. V v

:I-norder to more: thoroughly interiningle the ingredicntsot the charge-(a suitable agitator onay be provided for: mixing the material inthe innermost-r or chargingchamber. This chamber-is therefore in. efiiectv-a mixing: chain-berjas Well -.asa charging chamber. llheragitator --is conventionally illustrated son of. the highh'eat imparted to it-fr-oin the herein. as'a rotary stirrer comprising-a nuni- 7 her (of {blades 54:5 which are carried sat 1 the of said conduit.

introduced produces which; producest-hegaseous product, such as,

"Yet-01ft and. its :cover.

- avoided.

for the outer receptacle.

lower endofavertical shaft 46 whichcextends axially upwardly through the charging con duit :25 of the hood QGJandZ isjournalled suitable bearing 47' in the. closed upper end The charge 1may be\ antroduced into the charging'zconduit anmany suitable; manner through a passage id-pro- 'vided, with a removable, or preferably hinged, cover 4:9 hav'ing locking means-5O for retaining the cover firmly in placeibetween the chargingoperations, or suitable means may be provided for :d'el-1vering the charge contlnuously rnto theunnerino'stor V chargingchamber. V v 1 In u u l l t'll t' "t types or ,cisi a 1011 .appaia us,

such, for -example, usthose for-producing "nitric acid the nurtures ofchenncals, such I as sodium nitrate and sulphuric acid: are introduced in theh'rst instanceintoacool-1e: tort {and subsequentlyinto retorts Which-are more or less heated. The-fresh-charge'thus= ;;a violent reaction nitric aciid, so rapi'dly thatmn excessivepressureis produced in the retort duringthezso calied blowing i stage Whichus likely to "disruptthe apparatus, or toi't'orce the-anaterial through the joints between the shell lot the requires the use of large condensersyand other apparatus for; handling the ;.prold'uct.

'Furthermore. if the cold. charge is intro- This "rapidprof'duction not the gaseous product, such as; nitric ,aeld,

ducedi into a hot retortthea'lternate contraction and expansion is likelyto crack'the-re= tort. By the; present invention these under sir-able conditions are eliminated.

EWhere the retort is operated continuously the progressive introduction of chargeuin' small quantities prevents the productionot a violent reaction and. produces iawsubstantiallyunit'orin 'dischargeFof the gaseous prod- -uct b0t-h,1n the preliminary stagewand also 3111 the final stage; of distillation, tl1L1S58D- chli-ng much smaller condensing;apparatus to beused. ThQIBSlClUUDl'lS, gradually discharged through-the outletin proportion to" the introduction of the lreshinaterial. The heating of the retort 1SifiilntaillledCOHStHlt :and the loss of fuel, caused by cutting-off o1 drawing the dire to permit cooling of the apparatus and the necessary "reheating," is

If the apparatus is operated ;-inter1nittently the spent residueurina ybe;tapped off throughthe lower outlet/8. hen aif resh charge is introduced it Will d-isplacethe "charge in the inner receptacle into the router receptacle Which-thereupon tornis ajacket' The chargethus being introduced is first-plunged into the heatedmaterial, Within'the innermost chanu her and does-not come directly intocontact 7 with the shell of the innerreceptacle. 1t, t-heretore not only isnot subjected tovavhigh preliminary heat, but is gradually heated so that a less violent reaction takes place than in usual distillation apparatus. Furthermore, in both the continuous and intermittent operations of the apparatus the shell of the inner receptacle is protected against the direct heat of the furnace by the enclosing jacket formed by the shell of the outer receptacle. Thus corrosive action, which results from the contact of a highly heated shell with the freshly formed acid, is avoided.

In the present apparatus the heating of the material in the successive chambers is facilitated by reason of the fact that the liquid in passing from one chamber to the next is caused to flow along and in intimate contact with the shell of the inner container. The cylindrical portion ll of the hood 26 may be so constructed and proportioned as to collect and deliver the pure product of distillation, while the more impure acid or other distillate, which may be decomposed by long contact with the hot walls of the retort, is separately collected and delivered.

Various other advantageous features of the present invention will be obvious to those skilled in the art.

In Fig. 2 an embodiment of the present invention is illustrated as comprising a series of retorts of the character above described which are not provided with hoods for de livering the gas from a pluralityof chambers, but in which the charge is introduced into an inner or charging chamber within the inner container and-caused to flow up wardly along the walls thereof and to be discharged into the outer container so that the freshly introduced charge is prevented from contact with the wall of the container to which the direct heat is applied.

The construction disclosed herein com-- prises a preliminary distillation apparatus having an outer shell 51 with a suitable cover 52 having a charging opening 53 and an outlet 54 for the distillate and an inner container 55 preferably concentric with and spaced apart from the shell of the container. An annular partition 56 within the inner container provides a charging chamber and suitable apertures 57 in the bottom portion of the partition serve to conduct the liquid of the charge along the wall of the inner container. The partition 56 is of greater height than the wall of the inner container so that the charge will gradually overflow the edge thereof into the outer container. A conduit leading from the bottom of the outer container and extending substantially to the level of the top of the inner container leads to a second retort 58 of similar construction having an outlet 59 for the distillate and an outlet 60 for the residuum.

In the operation of this type of apparatus the pure distillate is discharged from the first retort, while the distillate from the partially spent charge is collected and delivered from the second retort. Obviously any number of retorts of this character may be employed within the spirit and scope of the claims which are intended broadly to cover a distillation apparatus having a series of chambers through which the charge is progressively passed with means for progressively heating the material during its passage'and means for delivering the distill-ate either from the retort as a whole or fractionally from selected chambers. The invention further embraces broadly any type of apparatus comprising an inner and an outer container in which a charge delivered into the inner container is caused to flow into the outer container and to produce a liquid jacket for the inner container which will prevent direct application of the heat to the wall of the inner container for the purposes hereinbefore described.

Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is:

1. A distillation apparatus comprising a retort having a series of chambers, means permitting the charge of material to pass progressively through said chambers, means for progressively heating the material during its passage, means for delivering the distillate and means selectively operable to deliver the residuum either continuously or intermittently, said means comprising a branched outlet from the outermost chamber one branch of said outlet being on a level with the bottom of said chamber and having a valve and the other branch of the outlet extending upwardly and opening at a predetermined distance above the bottom of said chamber.

2. A distillation apparatus comprising a o. A distillation apparatus comprising a furnace wholly enclosing a retort having a plurality of concentric chambers, an inlet into the innermost chamber and an outlet from the outermost chamber positioned to retain a predetermined amount of material, means for causing the pressure of the material in each chamber to exceed that in the next outer chamber whereby the material will be caused to flow from the innermost chamber a upwardly through "the surrounding chambers and its temperature progressively increased, means :for dellvcringthe distlllate produced bys:chemical reaction in the inner 5 chambers and separate means for dellvering.

the distillate produced in the outermost chamber in Which the material is subjected to therheat of the furnace.

distillation apparatus comprising. a

retort having, a plurality of concentric communicating chambers an lnlet 111130 the innermost chamber and an outlet from the outermost'chamber positioned to retain a predetermined: amount of material therein, the vvalluo't each inner chamber being; higher than-thevvallot the next outer-chamber, whereby: each inner chamber may be filled to-:a-higher level than the next outer chamberi'and caused to overflow by gravity into the next-outer chamber, means for heating, the vvall of the outermost chamber, a hood, having a peripheral wall extending lIliiOllhB' material in anrinner chamber for collecting and delivering the1d1stillate produced by chemical reaction 1n said inner chamber and meansiforideliveringrthe distillate produced in theoutermost chamber.-

5; Adistillation apparatus comprislng a retort having: an outer container and an "inner container annular ribs forming'hori- 'zontal shoulders, a series of partitions dividing said inner container into a series of concentric chambers, means for charging material -into. the innermost chamber, said partisaid inner container acting to permitthe material to flow progressively outwardly rfrom-geach inner chamber along-and in close" proximity, to the wallet said inner container andfmeans for; supplying heat to the Wall 7 of the outer container. 7

6. distillation apparatus CODIPITlSlIlg wa furnaceg-a '[retort Wholly enclosed; Within said furnaceihaving an 1I11161'"b()l*\lSl1&pGd 001191 *ta ner, .a SeIHeS'Ol partitions dividing. said container into a series oat concentric cham- -b;ers,- the g; outer of said partitions having a dome-:tocollect and deliver the distillate produced; in. the chamber enclosed thereby,

imityto the curved Wall of saidinner con- "tainer and an outer bowlshaped container substantiallyconcentric with said inner containervvholly enclosing the same and arranged to receive 7 material discharged from the inner. container and to form a jacketi.

'i'or saidfinner container and means for-def livering the distillate produced in said outer container; a 7. .A. distillation apparatus comprising a r-e'tort'i having an externally heated bowlshiapedlouter, container, a: bowl-shaped inner tionsfhaving recesses adjacent the Walls of means for charging material into theinner most chamber, means for causing the mate-- rial to flOW nrogressively outwardly fromeach inner chamber along and in close proxinner container and providedywith meansriforrsm V directing. the material aalongythewvall of thee inner container; andseparate means-for deelivering; the zdistillate collected by: said: hood from that produced in therouteracontainen'v 8. A distillation apparatusacomprising axBG: retort having; an externally heated.,'bovvlx shaped: outer container; a bovvil shaped' in;- ner container havingflai Wall lower than that 1 of the outer container located concentrically, Within said outer. container and'ispaced theree from, an annular partition: located centrally Within I said inner container and: iomningxza charge-receiving chamber, saidannularpan titionhaving aperturesiadj acent to itsnjunctionwith the; Wallof said: inner container; to:

permit material to :fioivfrom: the: charge-row ceiving chamber upwardly ttlOIlgztherWall off the; inner. container and to overfloww into? the outer container,v a hood having; an .an--

nular Wall depending into the: space betweenin said annular partitionwand. the Wall of said; inner (container and provided with means for: directing the material along thewvall ofth'e: inner container separate means -iondeliver ing thedistillate: collected by; said hood'ffromo 10 i that produced in the outer container andiianr' inlet leading through. said hood to; the chargereceiving chamber; v

9. 'Anapparatus of theqclass described? comprising acontainer dividedinto a plus ralityo't: concentricv communicating chain bers an inlet into theinnermost chamberv and a' 'branched outlet I from; i the outermost: chamber, wherebythexcharge is madeito move through the container fromthev center out1; 11 5 Ward, one branch of said" outlet-beingcorriaa" level With the bottom of the outermost chain V her-and the other branchot said aoutlet open:v ing" at a predetermined distance abovevthew bottom of said chamber, and anvalverirrisaidi120, V first mentioned branclradapted to be-opened orclosedto permit the apparatus to beopere ated either'continuously or intermittently r V 10.v An apparatus 'o-fthe: class described;

comprisinganouter containen an inner cons. j

tainer disposed Within the 1 outer container 1 and spaced theretrom an inlet into theinner container and abranchedoutlet fromothe outer container, and a' :valve-diwosed. in one branch of said. outletwherebytheispace be-i= 1'30 tween the inner container and the outer container may be emptied Without the removal of the contents of the inner container.

11. An apparatus for treatment of nitrates and sulphuric acid comprising, an outer container, an inner container disposed Within the outer container and spaced therefrom, said containers having their upper ends disposed in non-communicative relation with each other, an inlet into the inner container for said nitrates and sulphuric acid, an outlet from the space between the inner container and the outer container for the residuum, and individual vapor outlets from the upper portions of the two containers, the vapor outlet of the inner container being eX- tended through the outer container.

In testimony whereof, I have signed my name to this specification.

EARL R. HAMILTON. 

